Process for heat sealing polyurethane foam

Abstract

The instant invention is directed to a process for heat sealing flexible polyurethane foam, comprising: A. reacting and foaming a polyurethane foam produced by the steps comprising reacting: (I) an organic polyisocyanate; (II) a polyol having a molecular weight of 2,000 to 8,000 comprising the adduct obtained by sequentially reacting: (a) a polyhydroxyl initiator, with a functionality of 2 to 5 and a weight average molecular weight as determined by gel permeation chromatography of from 62 to 200; with (b) 10 to 90%, most preferably 10 to 50%, by weight, based on the total oxide present in (b)+(c)+(d), a first alkylene oxide; and subsequently reacting the product with (c) 10 to 80%, preferably 20 to 50% by weight, based on the total oxide present in (b)+(c)+(d), 4,4,4-trichloro-1,2-epoxybutane and/or epihalohydrin; and subsequently reacting the product with (d) 10 to 60%, most preferably 10 to 40%, by weight, based on the total oxide present in (b)+(c)+(d), a second alkylene oxide. (III) foaming agent; and optionally (IV) catalyst; B. heating a portion of the surface of said flexible polyurethane foam of (A) above its melting or fusion point; and C. cooling said flexible polyurethane foam below its melting or fusion point.

What is claimed is: 
     
       1. A process for heat sealing flexible polyurethane foam to a substrate comprising: A. reacting and foaming a flexible polyurethane foam produced by the steps comprising reacting: (I) an organic polyisocyanate;   (II) a polyol having a molecular weight of 2,000 to 8,000 comprising the adduct obtained by sequentially reacting: (a) a polyhydroxyl initiator, with a functionality of 2 to 5 and a weight average molecular weight as determined by gel permeation chromatography of from 50 to 200; with   (b) 10 to 90%, by weight based on the total oxide present in (b)+(c)+(d), a first alkylene oxide; and subsequently reacting the product with   (c) 10 to 80%, by weight, based on the total oxide present in (b)+(c)+(d), 4,4,4-trichloro-1,2-epoxybutane and/or epihalohydrin; and subsequently reacting the product with   (d) 10 to 60%, by weight, based on the total oxide present in (b)+(c)+(d), a second alkylene oxide;     (III) foaming agent; and optionally   (IV) catalyst;     B. allowing said resulting polyurethane foam to cure;   C. heating a portion of the surface of said flexible polyurethane foam of (B) above its melting or fusion point; and   D. contacting the melted or fused surface of said polyurethane flexible foam with a substrate whereby a flexible polyurethane foam/substrate laminate is formed; and   E. cooling said flexible polyurethane foam/substrate laminate below the melting or fusion point of said foam.   
     
     
       2. The process of claim 1 wherein said alkylene oxide of (b) and (d) is ethylene oxide and/or propylene oxide. 
     
     
       3. The process of claim 1, wherein said polyhydroxyl initiator (a) has a functionality of 3. 
     
     
       4. The process of claim 3, wherein said polyhydroxyl initiator (a) is glycerol. 
     
     
       5. The process of claim 1, wherein said organic polyisocyanate (I) is toluene diisocyanate. 
     
     
       6. The process of claim 1, wherein component (c) is 4,4,4-trichloro-1,2-epoxybutane. 
     
     
       7. The process of claim 1, wherein component (c) is epihalohydrin. 
     
     
       8. The process of claim 1, wherein said polyol has a molecular weight of 5,500 to 7,000. 
     
     
       9. The process of claim 1, wherein component (b) is 10 to 50%;   (c) is 20 to 50%; and   (d) is 10 to 40%.   
     
     
       10. A process for melting or fusing portions of flexible polyurethane foam, comprising: A. preparing a polyurethane foam by the steps comprising reacting: (I) an organic polyisocyanate;   (II) a polyol having a molecular weight of 2,000 to 8,000 comprising the adduct obtained by sequentially reacting: (a) a polyhydroxyl initiator, with a functionality of 2 to 5 and a weight average molecular weight as determined by gel permeation chromatography of from 62 to 200; with   (b) 10 to 90%, by weight, based on the total oxide present in (b)+(c)+(d), a first alkylene oxide; and subsequently reacting the product with   (c) 10 to 80%, by weight, based on the total oxide present in (b)+(c)+(d), 4,4,4-trichloro-1,2-epoxybutane and/or epihalohydrin; and subsequently reacting the product with   (d) 10 to 60%, by weight, based on the total oxide present in (b)+(c)+(d), a second alkylene oxide;     (III) foaming agent; and optionally   (IV) catalyst;     B. allowing said resulting polyurethane foam to cure;   C. heating a portion of the surface of said flexible polyurethane foam of (B) above its melting or fusion point; and   D. cooling said flexible polyurethane foam below its melting or fusion point.   
     
     
       11. The process of claim 10 wherein said alkylene oxide of (b) and (d) is ethylene oxide and/or propylene oxide. 
     
     
       12. The process of claim 10, wherein said polyhydroxyl initiator (a) has a functionality of 3. 
     
     
       13. The process of claim 12, wherein said polyhydroxyl initiator (a) is glycerol. 
     
     
       14. The process of claim 10, wherein said organic polyisocyanate (I) is toluene diisocyanate. 
     
     
       15. The process of claim 10, wherein component (c) is 4,4,4-trichloro-1,2-epoxybutane. 
     
     
       16. The process of claim 10, wherein component (c) is epihalohydrin. 
     
     
       17. The process of claim 10, wherein said polyol has a molecular weight of 5,500 to 7.000. 
     
     
       18. The process of claim 10, wherein component (b) is 10 to 50%;   (c) is 20 to 50%; and   (d) is 10 to 40%.